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Zombie Card Attack Can Revive Expired Visa Cards for Contactless Payments

UMass Amherst researchers demonstrate Zombie Card, an NFC relay attack that revives expired Visa contactless cards for in-store purchases without breaking cryptography.

Researchers at the University of Massachusetts Amherst presented the Zombie Card attack at USENIX Security 2026, showing that Visa's Kernel 3 does not cryptographically bind the Application Expiration Date (tag 5F24) the terminal reads with the Track 2 expiry seen by the issuer. By positioning an NFC man-in-the-middle relay, an attacker can rewrite the terminal-facing expiration date of an expired card and complete contactless purchases, provided the account remains open under the same PAN and the bank does not independently re-check expiry. Testing across five major US banks found three distinct policies; Visa Kernel 3 accepted the modified date, while Mastercard, American Express, and Discover kernels declined modified transactions. Findings were disclosed to Visa and affected banks in May 2025, no CVE has been assigned, and no exploitation has been reported.

The Hacker News · 27d agoResearch

Google Password Manager Attacks Could Let Malware Hijack Passkey

Unit 42 details three attack paths letting Windows malware silently sign into passkey-protected accounts via Chrome's Google Password Manager without user verification.

Palo Alto Networks Unit 42 described three post-compromise attack paths—Pass-ta-key, Silver Pass-ta-key and Golden Pass-ta-key—against Chrome's Google Password Manager cloud authenticator on TPM-equipped Windows systems. The attacks can silently obtain valid authentication assertions, install attacker-controlled user-verification keys, or extract the 32-byte Security Domain Secret used to decrypt synced passkey private keys, enabling reusable access from the attacker's own environment. No CVE was assigned and no exploitation in the wild was reported; demonstrations were validated against Chrome 142 and parts of the architecture are corroborated by Chromium source. GitHub enforced the User Verified flag check, while eBay accepted a test assertion lacking it before fixing its validation gap after disclosure.

The Hacker News · Aug 11, 2026Research

Risky Bulletin: Expired cards can be used for new transactions

Researchers show expired Visa contactless cards can be revived via NFC man-in-the-middle relay to run fraudulent transactions; roundup also covers major breaches.

University of Massachusetts Amherst researchers built an NFC man-in-the-middle rig that updates a card's expiration date in transit and relays the modified payment to POS terminals, reviving expired contactless cards; Visa terminals and the backends of all five banks studied failed to catch the manipulation. The same roundup reports Iranian hackers shut down a small UK power plant for four days, Lazarus breached South Korea's Presidential Office as part of a campaign exceeding 100 victims, and French telecom SFR suffered a breach affecting over 2.1 million customers.

Risky Business News · 23d agoResearch1